Hydrochloric Acid → trans-1-Hydroxy-spiro[5.5]undecane-2-carboxylic acid methyl ester

Beteiligte Stoffe

Reaktionsschritte

To a solution of 1-oxo-spiro[5.5]undecane-2-carboxylic acid methyl ester (13.02 g) obtained in Step 2 in methanol (300 mL), sodium borohydride (2.2 g) was added in small portions under ice-cooling, followed by stirring the reaction mixture under ice-cooling for 30 minutes. Then, after addition of saturated brine, 2N aqueous hydrochloric acid solution was further added dropwise to the reaction mixture until the evolution of gases ceased, followed by extraction with ethyl acetate twice. The organic layer was washed with saturated brine, dried and concentrated. The residue was purified by column chromatography on silica gel (ethyl acetate:hexane (volume ratio)=1:8 to 1:5) to give trans-1-hydroxy-spiro[5.5]undecane-2-carboxylic acid methyl ester (2.74 g).

Herkunft & Nachweise